The present disclosure generally relates to capturing devices or cameras used in virtual reality (VR), augmented reality (AR) and mixed reality (MR) systems, and specifically relates to implementation of light field cameras using an angle sensitive pixel array that includes a liquid crystal layer.
A light field camera captures information about a light field emanating from a scene, i.e., the light field camera captures information about intensity of light reflected from the scene and information about angles of light rays reflected from the scene. In contrast, a conventional camera captures only light intensity. Light field cameras can be used in VR, AR and MR systems for, for example, three-dimensional (3D) or depth estimation of objects in a scene, and for eye tracking. Typically, a light field camera employs an array of micro-lenses placed in front of a conventional image sensor or pixel array for sensing intensity, color and directional (angle) information. However, implementation of a light field camera based on an array of micro-lenses does not provide flexibility in controlling an amount of light that propagates the array of micro-lenses at a given angle. This is because an array of micro-lenses passes light having particular angular direction(s), wherein light rays that propagate in other angular directions are not passed through the array of micro-lenses and information about these angular directions is lost. In addition, flexibility in controlling amounts of light that reach a pixel array of a light field camera at different angles require micro-lens arrays of different orientations to overlay the pixel array. Therefore, it is desirable to achieve more flexible implementation of a light field camera.